This program will produce a new system for detecting ferromagnetic foreign bodies (FFBs) in the eye, brain and other tissues. This system will be useful in screening patients for FFBs prior to magnetic resonance imaging (MRI), as well as varifying the MRI safety of medical implants. The new system detects the magnetic moment induced in the FFB by a weak ac magnetic field. Unlike X-rays and CT scans, this method involves no ionizing radiation, and it distinguishes ferromagnetic from non-ferromagnetic materials. This capability will reduce the risk of injury and eliminate the need to deny MRI to patients with unidentified metallic foreign bodies. During Phase I, we showed that ac magnetic measurements could detect small ferromagnetic bodies at distances sufficient to screen the eye and orbit. We also developed methods to distinguish the signature of the FFB from the background signal due to the patient s head. During Phase II, we will increase the sensitivity of the measurements, enhance our techniques for rejecting the head background, develop an improved instrument for clinical studies, and demonstrate sensitivity and selectivity through controlled trials on animal subjects. PROPOSED COMMERCIAL APPLICATION This new technology may be used in every one of the 2500-3500 MRI centers in the United States alone. It will reduce costs, minimize risks, eliminate uncertainties, and make MRI more accessible to patients with prior injuries or medical implants. To develop this potential, Quantum Magnetics has formed a partnership with Dr. R. Kemp Massengill, an entrepreneur who has successfully marketed ultrasonic liposuction and low-cost phacoemulsification technology.